Inbred maize line NP2015

ABSTRACT

An inbred maize line, designated NP2015, the plants and seeds of inbred maize line NP2015, methods for producing a maize plant produced by crossing the inbred line NP2015 with itself or with another maize plant, and hybrid maize seeds and plants produced by crossing the inbred line NP2015 with another maize line or plant.

FIELD OF THE INVENTION

This invention is in the field of maize breeding, specifically relatingto an inbred maize line designated NP2015.

BACKGROUND OF THE INVENTION

The goal of plant breeding is to combine in a single variety or hybridvarious desirable traits. For field crops, these traits may includeresistance to diseases and insects, tolerance to heat and drought,reducing the time to crop maturity, greater yield, and better agronomicquality. With mechanical harvesting of many crops, uniformity of plantcharacteristics such as germination and stand establishment, growthrate, maturity, and plant and ear height, is important.

Field crops are bred through techniques that take advantage of theplant's method of pollination. A plant is self-pollinated if pollen fromone flower is transferred to the same or another flower of the sameplant. A plant is cross-pollinated if the pollen comes from a flower ona different plant. Plants that have been self-pollinated and selectedfor type for many generations become homozygous at almost all gene lociand produce a uniform population of true breeding progeny. A crossbetween two different homozygous lines produces a uniform population ofhybrid plants that may be heterozygous for many gene loci. A cross oftwo plants each heterozygous at a number of gene loci will produce apopulation of hybrid plants that differ genetically and will not beuniform.

Maize (Zea mays L.), often referred to as corn in the United States, canbe bred by both self-pollination and cross-pollination techniques. Maizehas separate male and female flowers on the same plant, located on thetassel and the ear, respectively. Natural pollination occurs in maizewhen wind blows pollen from the tassels to the silks that protrude fromthe tops of the ears.

A reliable method of controlling male fertility in plants offers theopportunity for improved plant breeding. This is especially true fordevelopment of maize hybrids, which relies upon some sort of malesterility system. There are several options for controlling malefertility available to breeders, such as: manual or mechanicalemasculation (or detasseling), cytoplasmic male sterility, genetic malesterility, gametocides and the like. Hybrid maize seed is typicallyproduced by a male sterility system incorporating manual or mechanicaldetasseling. Alternate strips of two maize inbreds are planted in afield, and the pollen-bearing tassels are removed from one of theinbreds (female). Providing that there is sufficient isolation fromsources of foreign maize pollen, the ears of the detasseled inbred willbe fertilized only from the other inbred (male), and the resulting seedis therefore hybrid and will form hybrid plants.

The laborious, and occasionally unreliable, detasseling process can beavoided by using cytoplasmic male-sterile (CMS) inbreds. Plants of a CMSinbred are male sterile as a result of factors resulting from thecytoplasmic, as opposed to the nuclear, genome. Thus, thischaracteristic is inherited exclusively through the female parent inmaize plants, since only the female provides cytoplasm to the fertilizedseed. CMS plants are fertilized with pollen from another inbred that isnot male-sterile. Pollen from the second inbred may or may notcontribute genes that make the hybrid plants male-fertile. Seed fromdetasseled fertile maize and CMS produced seed of the same hybrid can beblended to insure that adequate pollen loads are available forfertilization when the hybrid plants are grown. There are severalmethods of conferring genetic male sterility available, such as multiplemutant genes at separate locations within the genome that confer malesterility, as disclosed in U.S. Pat. Nos. 4,654,465 and 4,727,219 toBrar et al. and chromosomal translocations as described by Patterson inU.S. Pat. Nos. 3,861,709 and 3,710,511. These and all patents referredto are incorporated by reference.

There are many other methods of conferring genetic male sterility in theart, each with its own benefits and drawbacks. These methods use avariety of approaches such as delivering into the plant a gene encodinga cytotoxic substance associated with a male tissue specific promoter oran antisense system in which a gene critical to fertility is identifiedand an antisense to that gene is inserted in the plant (see:Fabinjanski, et al. EPO 89/3010153.8 publication no. 329,308 and PCTapplication PCT/CA90/00037 published as WO 90/08828).

Another system useful in controlling male sterility makes use ofgametocides. Gametocides are not a genetic system, but rather a topicalapplication of chemicals. These chemicals affect cells that are criticalto male fertility. The application of these chemicals affects fertilityin the plants only for the growing season in which the gametocide isapplied (see Carlson, Glenn R., U.S. Pat. No. 4,936,904). Application ofthe gametocide, timing of the application and genotype specificity oftenlimit the usefulness of the approach.

The use of male sterile inbreds is but one factor in the production ofmaize hybrids. The development of maize hybrids requires, in general,the development of homozygous inbred lines, the crossing of these lines,and the evaluation of the crosses. Pedigree breeding and recurrentselection breeding methods are used to develop inbred lines frombreeding populations. Breeding programs combine the genetic backgroundsfrom two or more inbred lines or various other germplasm sources intobreeding pools from which new inbred lines are developed by selfing andselection of desired phenotypes. The new inbreds are crossed with otherinbred lines and the hybrids from these crosses are evaluated todetermine which of those have commercial potential. Plant breeding andhybrid development are expensive and time consuming processes.

Pedigree breeding starts with the crossing of two genotypes, each ofwhich may have one or more desirable characteristics that is lacking inthe other or which complements the other. If the two original parents donot provide all the desired characteristics, other sources can beincluded in the breeding population. In the pedigree method, superiorplants are selfed and selected in successive generations. In thesucceeding generations the heterozygous condition gives way tohomogeneous lines as a result of self-pollination and selection.Typically in the pedigree method of breeding five or more generations ofselfing and selection is practiced: F1 to F2; F3 to F4; F4 to F5, etc.

A single cross maize hybrid results from the cross of two inbred lines,each of which has a genotype that complements the genotype of the other.The hybrid progeny of the first generation is designated F1. In thedevelopment of commercial hybrids only the F1 hybrid plants are sought.Preferred F1 hybrids are more vigorous than their inbred parents. Thishybrid vigor, or heterosis, can be manifested in many polygenic traits,including increased vegetative growth and increased yield.

The development of a maize hybrid involves three steps: (1) theselection of plants from various germplasm pools for initial breedingcrosses; (2) the selfing of the selected plants from the breedingcrosses for several generations to produce a series of inbred lines,which, although different from each other, breed true and are highlyuniform; and (3) crossing the selected inbred lines with differentinbred lines to produce the hybrid progeny (F1). During the inbreedingprocess in maize, the vigor of the lines decreases. Vigor is restoredwhen two different inbred lines are crossed to produce the hybridprogeny (F1). An important consequence of the homozygosity andhomogeneity of the inbred lines is that the hybrid between a definedpair of inbreds will always be the same. Once the inbreds that give asuperior hybrid have been identified, the hybrid seed can be reproducedindefinitely as long as the homogeneity of the inbred parents ismaintained. A single cross hybrid is produced when two inbred lines arecrossed to produce the F1 progeny. A double cross hybrid is producedfrom four inbred lines crossed in pairs (A×B and C×D) and then the twoF1 hybrids are crossed again (A×B)×(C×D). Much of the hybrid vigorexhibited by F1 hybrids is lost in the next generation (F2).Consequently, seed from hybrids is not used for planting stock.

Hybrid seed production requires elimination or inactivation of pollenproduced by the female parent. Incomplete removal or inactivation of thepollen provides the potential for self pollination. This inadvertentlyself pollinated seed may be unintentionally harvested and packaged withhybrid seed. Once the seed is planted, it is possible to identify andselect these self pollinated plants. These self pollinated plants willbe genetically equivalent to the female inbred line used to produce thehybrid. Typically these self pollinated plants can be identified andselected due to their decreased vigor. Female selfs are identified bytheir less vigorous appearance for vegetative and/or reproductivecharacteristics, including shorter plant height, small ear size, ear andkernel shape, cob color, or other characteristics.

Identification of these self pollinated lines can also be accomplishedthrough molecular marker analyses. See, “The Identification of FemaleSelfs in Hybrid Maize: A Comparison Using Electrophoresis andMorphology”, Smith, J. S. C. and Wych, R. D., Seed Science andTechnology 14, pp. 1-8 (1995), the disclosure of which is expresslyincorporated herein by reference. Through these technologies, thehomozygosity of the self pollinated line can be verified by analyzingallelic composition at various loci along the genome. Those methodsallow for rapid identification of the invention disclosed herein. Seealso, “Identification of Atypical Plants in Hybrid Maize Seed byPostcontrol and Electrophoresis” Sarca, V. et al., Probleme de GeneticaTeoritca si Aplicata Vol. 20 (1) p. 29-42.

As is readily apparent to one skilled in the art, the foregoing are onlytwo of the various ways by which the inbred can be obtained by thoselooking to use the germplasm. Other means are available, and the aboveexamples are illustrative only.

Maize is an important and valuable field crop. Thus, a continuing goalof plant breeders is to develop high-yielding maize hybrids that areagronomically sound based on stable inbred lines. The reasons for thisgoal are obvious: to maximize the amount of grain produced with theinputs used and minimize susceptibility of the crop to pests andenvironmental stresses. To accomplish this goal, the maize breeder mustselect and develop superior inbred parental lines for producing hybrids.This requires identification and selection of genetically uniqueindividuals that occur in a segregating population. The segregatingpopulation is the result of a combination of crossover events plus theindependent assortment of specific combinations of alleles at many geneloci that results in specific genotypes. The probability of selectingany one individual with a specific genotype from a breeding cross isinfinitesimal due to the large number of segregating genes and theunlimited recombinations of these genes, some of which may be closelylinked. However, the genetic variation among individual progeny of abreeding cross allows for the identification of rare and valuable newgenotypes. These new genotypes are neither predictable nor incrementalin value, but rather the result of manifested genetic variation combinedwith selection methods, environments and the actions of the breeder.

Thus, even if the entire genotypes of the parents of the breeding crosswere characterized and a desired genotype known, only a few, if any,individuals having the desired genotype may be found in a largesegregating F2 population. Typically, however, neither the genotypes ofthe breeding cross parents nor the desired genotype to be selected isknown in any detail. In addition, it is not known how the desiredgenotype would react with the environment. This genotype by environmentinteraction is an important, yet unpredictable, factor in plantbreeding. A breeder of ordinary skill in the art cannot predict thegenotype, how that genotype will interact with various climaticconditions or the resulting phenotypes of the developing lines, exceptperhaps in a very broad and general fashion. A breeder of ordinary skillin the art would also be unable to recreate the same line twice from thevery same original parents as the breeder is unable to direct how thegenomes combine or how they will interact with the environmentalconditions. This unpredictability results in the expenditure of largeamounts of research resources in the development of a superior new maizeinbred line.

SUMMARY OF THE INVENTION

According to the invention, there is provided a novel inbred maize line,designated NP2015. This invention thus relates to the seeds of inbredmaize line NP2015, to the plants of inbred maize line NP2015, and tomethods for producing a maize plant by crossing the inbred line NP2015with itself or another maize line. This invention further relates tohybrid maize seeds and plants produced by crossing the inbred lineNP2015 with another maize line.

The invention is also directed to inbred maize line NP2015 into whichone or more specific, single gene traits, for example transgenes, havebeen introgressed from another maize line and which have essentially allof the morphological and physiological characteristics of inbred maizeline of NP2015, in addition to the one or more specific, single genetraits introgressed into the inbred. The invention also relates to seedsof an inbred maize line NP2015 into which one or more specific, singlegene traits have been introgressed and to plants of an inbred maize lineNP2015 into which one or more specific, single gene traits have beenintrogressed. The invention further relates to methods for producing amaize plant by crossing plants of an inbred maize line NP2015 into whichone or more specific, single gene traits have been introgressed withthemselves or with another maize line. The invention also furtherrelates to hybrid maize seeds and plants produced by crossing plants ofan inbred maize line NP2015 into which one or more specific, single genetraits have been introgressed with another maize line.

DEFINITIONS

In the description and examples that follow, a number of terms are usedherein. In order to provide a clear and consistent understanding of thespecification and claims, including the scope to be given such terms,the following definitions are provided. Below are the descriptors usedin the data tables included herein. All linear measurements are incentimeters unless otherwise noted.

Heat units (Max Temp(<=86 deg. F.) + Min Temp(>=50 deg. F.))/2 − 50EMRGN Final number of plants per plot KRTP Kernel type: 1.sweet 2.dent3.flint 4.flour 5.pop 6.ornamental 7.pipecorn 8.other ERTLP % Rootlodging (before anthesis) GRNSP % Brittle snapping (before anthesis)TBANN Tassel branch angle of 2nd primary lateral branch (at anthesis)LSPUR Leaf sheath pubescence of second leaf above the ear (at anthesis)1-9 (1 = none) ANGBN Angle between stalk and 2nd leaf above the ear (atanthesis) CR2L Color of 2nd leaf above the ear (at anthesis) GLCR GlumeColor GLCB Glume color bars perpendicular to their veins (glume bands):1.absent 2.present ANTC Anther color PLQUR Pollen Shed: 0-9 (0 = malesterile) HU1PN Heat units to 10% pollen shed HUPSN Heat units to 50%pollen shed SLKC Silk color HU5SN Heat units to 50% silk SLK5N Days to50% silk in adapted zone HU9PN Heat units to 90% pollen shed HUPLN Heatunits from 10% to 90% pollen shed DA19 Days from 10% to 90% pollen shedLAERN Number of leaves above the top ear node MLWVR Leaf marginal waves:1-9 (1 = none) LFLCR Leaf longitudinal creases: 1-9 (1 = none) ERLLNLength of ear leaf at the top ear node ERLWN Width of ear leaf at thetop ear node at the widest point PLHCN Plant height to tassel tip ERHCNPlant height to the top ear node LTEIN Length of the internode betweenthe ear node and the node above LTASN Length of the tassel from top leafcollar to tassel tip LTBRN Number of lateral tassel branches thatoriginate from the central spike EARPN Number of ears per stalk APBRRAnthocyanin pigment of brace roots: 1.absent 2.faint 3.moderate 4.darkTILLN Number of tillers per plant HSKC Husk color 25 days after 50% silk(fresh) HSKD Husk color 65 days after 50% silk (dry) HSKTR Husktightness 65 days after 50% silk: 1-9 (1 = loose) HSKCR Husk extension:1.short (ear exposed) 2.medium (8 cm) 3.long (8-10 cm) 4.very long (>10cm) HEPSR Position of ear 65 days after 50% silk: 1.upright 2.horizontal3.pendent STGRP % Staygreen at maturity DPOPN % dropped ears 65 daysafter anthesis LRTRN % root lodging 65 days after anthesis HU25 Heatunits to 25% grain moisture HUSG Heat units from 50% silk to 25% grainmoisture in adapted zone DSGM Days from 50% silk to 25% grain moisturein adapted zone SHLNN Shank length ERLNN Ear length ERDIN Diameter ofthe ear at the midpoint EWGTN Weight of a husked ear (grams) KRRWRKernel rows: 1.indistinct 2.distinct KRNAR Kernel row alignment:1.straight 2.slightly curved 3.curved ETAPR Ear taper: 1.slight2.average 3.extreme KRRWN Number of kernel rows COBC Cob color COBDNDiameter of the cob at the midpoint KRTP Endosperm type: 1.sweet 2.extrasweet 3.normal 4.high amylose 5.waxy 6.high protein 7.high lysine8.super sweet 9.high oil 10.other KRCL Hard endosperm color ALECAleurone color ALCP Aleurone color pattern: 1.homozygous 2.segregatingKRLNN Kernel length (mm) KRWDN Kernel width (mm) KRDPN Kernel thickness(mm) K100N 100 kernel weight (grams) KRPRN % round kernels on 13/64slotted screen GRLSR Grey leaf spot severity rating; 1=resistent,9=susceptible. INTLR Intactness rating of plants at time of harvest;1=all foliage intact, 9=all plants broken below the ear. LRTLPPercentage of plants lodged, leaning >30 degrees from vertical, butunbroken at harvest. MST_P Percent grain moisture at harvest. SCLBRSouthern corn leaf blight severity rating; 1=resistent, 9=susceptible.STKLP Percentage of plants with stalks broken below the ear at time ofharvest. YBUAN Grain yield expressed as bushels per acre adjusted to15.5% grain moisture.

DETAILED DESCRIPTION OF THE INVENTION

Inbred maize lines are typically developed for use in the production ofhybrid maize lines. Inbred maize lines need to be highly homogeneous,homozygous and reproducible to be useful as parents of commercialhybrids. There are many analytical methods available to determine thehomozygotic and phenotypic stability of these inbred lines. The oldestand most traditional method of analysis is the observation of phenotypictraits. The data is usually collected in field experiments over the lifeof the maize plants to be examined. Phenotypic characteristics mostoften observed are for traits associated with plant morphology, ear andkernel morphology, insect and disease resistance, maturity, and yield.

In addition to phenotypic observations, the genotype of a plant can alsobe examined. There are many laboratory-based techniques available forthe analysis, comparison and characterization of plant genotype; amongthese are Isozyme Electrophoresis, Restriction Fragment LengthPolymorphisms (RFLPs), Randomly Amplified Polymorphic DNAs (RAPDs),Arbitrarily Primed Polymerase Chain Reaction (AP-PCR), DNA AmplificationFingerprinting (DAF), Sequence Characterized Amplified Regions (SCARs),Amplified Fragment Length Polymorphisms (AFLPs), and Simple SequenceRepeats (SSRs) which are also referred to as Microsatellites.

Some of the most widely used of these laboratory techniques are IsozymeElectrophoresis and RFLPs as discussed in Lee, M., “Inbred Lines ofMaize and Their Molecular Markers,” The Maize Handbook,(Springer-Verlag, New York, Inc. 1994, at 423-432) incorporated hereinby reference. Isozyme Electrophoresis is a useful tool in determininggenetic composition, although it has relatively low number of availablemarkers and the low number of allelic variants among maize inbreds.RFLPs have the advantage of revealing an exceptionally high degree ofallelic variation in maize and the number of available markers is almostlimitless. Maize RFLP linkage maps have been rapidly constructed andwidely implemented in genetic studies. One such study is described inBoppenmaier, et al., “Comparisons among strains of inbreds for RFLPs”,Maize Genetics Cooperative Newsletter, 65:1991, pg. 90, is incorporatedherein by reference. This study used 101 RFLP markers to analyze thepatterns of 2 to 3 different deposits each of five different inbredlines. The inbred lines had been selfed from 9 to 12 times before beingadopted into 2 to 3 different breeding programs. It was results fromthese 2 to 3 different breeding programs that supplied the differentdeposits for analysis. These five lines were maintained in the separatebreeding programs by selfing or sibbing and rogueing off-type plants foran additional one to eight generations. After the RFLP analysis wascompleted, it was determined the five lines showed 0-2% residualheterozygosity. Although this was a relatively small study, it can beseen using RFLPs that the lines had been highly homozygous prior to theseparate strain maintenance.

Inbred maize line NP2015 is a yellow dent maize inbred that is bestsuited as a male in crosses for producing first generation F1 maizehybrids. Inbred maize line NP2015 is best adapted to the Northwest,Northcentral and Northeast regions of the United States and the CornBelt region of Canada and can be used to produce hybrids fromapproximately 92-100 relative maturity based on the Comparative RelativeMaturity Rating System for harvest moisture of grain. Inbred maize lineNP2015 demonstrates reliable late season plant health and good pollenshed. In hybrid combinations, NP2015 demonstrates high yield for itsmaturity, above average seedling vigor, medium plant stature, aboveaverage plant health, and has an attractive plant appearance. In hybridcombinations, NP2015 also demonstrates above average resistance toNorthern Leaf Blight, average resistance to Eyespot, and superiorresistance to first and second generations of European Corn Borer. Forits area of adaptation, NP2015 demonstrates high yields, resistance toleaf diseases, consistent late season plant health, and reliableseedling vigor.

Inbred maize line NP2015 was derived from the cross of inbred line 807and inbred line L8754. Both of the parents of NP2015 were developed andare owned by Novartis Seeds, Inc. Inbred line 807 is proprietary. Inbredline L8754 was selfed from the Pioneer hybrid 3790. After development ofthe S₀ (or F₂) population of 807×L8754, the breeding method was simplepedigree ear-to-row development of inbred NP2015. Inbred maize lineNP2015 has shown uniformity and stability within the limits ofenvironmental influence for all the traits as described in the VarietyDescription Information (Table 1) that follows. The inbred has beenself-pollinated and ear-rowed a sufficient number of generations withcareful attention paid to uniformity of plant type to ensure thehomozygosity and phenotypic stability necessary to use in commercialproduction. The line has been increased both by hand and in isolatedfields with continued observation for uniformity. No variant traits havebeen observed or are expected in NP2015. Inbred maize line NP2015, beingsubstantially homozygous, can be reproduced by planting seeds of theline, growing the resulting maize plants under self-pollinating orsib-pollinating conditions with adequate isolation, and harvesting theresulting seed, using techniques familiar to the agricultural arts.

The production of hybrid maize lines typically comprises planting inpollinating proximity seeds of, for example, inbred maize line NP2015and of a different inbred parent maize plant, cultivating the seeds ofinbred maize line NP2015 and of said different inbred parent maize plantinto plants that bear flowers, emasculating the male flowers of inbredmaize line NP2015 or the male flowers of said different inbred parentmaize plant to produce an emasculated maize plant, allowingcross-pollination to occur between inbred maize line NP2015 and saiddifferent inbred parent maize plant and harvesting seeds produced onsaid emasculated maize plant. The harvested seed are grown to producehybrid maize plants.

Inbred maize line NP2015 can be crossed to inbred maize lines of variousheterotic group (see e.g. Hallauer et al. (1988) in Corn and CornImprovement, Sprague et al, eds, chapter 8, pages 463-564, incorporatedherein by reference) for the production of hybrid maize lines.

TABLE 1 VARIETY DESCRIPTION INFORMATION Inbred maize line NP2015 iscompared inbred CM105 INBRED NP2015 INBRED CM105 MATURITY Days HeatUnits Days Heat Units From emergence to 50% of plants in silk 63 1202.663 1180.9 From emergence to 50% of plants in pollen 63 1196.6 62 1160.8From 10% to 90% pollen shed 3 57.3 3 59.4 PLANT Std Dev Sample Size StdDev Sample Size cm Plant Height (to tassel tip) 162.7 18.32 55 171.416.56 50 cm Ear Height (to base of top ear node) 64 7.32 55 59.4 8.3 50cm Length of Top Ear Internodenode 11.1 1.77 11 12.6 1.98 10 AverageNumber of Tillers .3 .71 9 .1 .35 8 Average Number of Ears per Stalk 1.3.47 11 1.2 .37 10 Anthocyanin of Brace Roots: 3 3 1 = Absent 2 = Faint 3= Moderate 4 = Dark LEAF Std Dev Sample Size Std Dev Sample Size cmWidth of Ear Node Leaf 9 .75 55 7.6 .62 10 cm Length of Ear Node Leaf 678.77 55 79.2 6.78 Number of leaves above top ear 6 .4 55 6 .85 10degrees Leaf Angle 41 13.64 9 49 11.8 7 (measure from 2nd leaf above earat anthesis to stalk above leaf) Leaf Color 3 (Munsell code 5GY 4/6) 3(Munsell code 5GY 4/6) Leaf Sheath Pubescence 3 6 (Rate on scale from1 + none to 9 = like peach fuzz) Marginal Waves 6 6 (Rate on scale from1 = none to 9 = many) Longitudinal Creases 3 3 (Rate on scale from 1 =none to 9 = many) TASSEL Std Dev Sample Size Std Dev Sample Size Numberof Primary Lateral Branches 8 1.6 11 5 2.37 10 Branch Angle from CentralSpike 41 11.5 10 45 8.02 8 Cm Tassel Length 23.6 10.09 11 32.2 3.33 8(from top leaf collar to tassel tip) Pollen Shed 6 6 (Rate on scale from0 = male sterile to 9 = heavy shed) Anther Color 6 (Munsell code 5Y 8/6)5 (Munsell code 2.5GY 7/4) Glume Color 5 (Munsell code SGY 6/8) 2(Munsell code SGY 5/6) Bar Glumes (Glume Bands): 1 = Absent 2 = Present1 1 EAR (Unhusked Data) Silk Color (3 days after emergence) 16 (Munsellcode 5RP 6/8) 5 (Munsell code 2.5GY 8/10) Fresh Husk Color (25 daysafter 50% silking) 1 (Munsell code 2.5GY 7/6) 2 (Munsell code 5GY 6/8)Dry Husk Color (65 days after 50% silking) 7 (Munsell code 2.5Y 7/10) 22(Munsell code 2.5Y 8/6) Position of Ear at Dry Husk Stage: 1 3 1 =Upright 2 = Horizontal 3 = Pendent Husk Tightness 4 4 (Rate on scalefrom 1 = very loose to 9 = very tight) Husk Extension (at harvest): 2 21 = Short (ears exposed) 2 = Medium (<8 cm) 3 = Long (8-10 cm beyond eartip) 4 = Very long (>10 cm) EAR (Husked Ear Data) Std Dev Sample SizeStd Dev Sample Size cm Ear Length 14.8 1.64 11 13.3 2.07 9 mm EarDiameter at mid-point 39.3 2.06 11 35.2 2.2 9 gm Ear Weight 119.7 27.3811 80.5 21.19 9 Number of Kernel Rows 12 1.13 11 13 1.49 9 Kernel Rows:1 = Indistinct 2 = Distinct 2 2 Row Alignment: 1 1 1 = Straight 2 =Slightly Curved 3 = Spiral cm Shank Length 11.5 4.44 11 9.2 3.12 9 EarTaper: 1 = Slight 2 = Average 3 = Extreme 2 2 KERNEL (Dried) Std DevSample Size Std Dev Sample Size mm Kernel Length 11.3 .65 11 9.3 1 9 mmKernel Width 8.7 .47 11 7.6 .53 9 mm Kernel Thickness 3.8 .6 11 4 .5 9 %Round Kernels (Shape Grade) 18.4 9.3 11 22.7 17.35 9 Aleurone ColorPattern: 1 1 1 = Homozygous 2 = Segregating Aleurone Color 12 (Munsellcode 5YR 7/6) 10 (Munsell code 5YR 7/6) Hard Endosperm Color 8 (Munsellcode 7.5YR 6/10) 8 (Munsell code 7.5YR 6/10) Endosperm Type: 3 3 1 =Sweet (sul) 2 = Extra Sweet (sh2) 3 = Normal Starch gm Weight per 100Kernels (unsized sample) 32 4.32 11 21.6 5.39 9 COB Std Dev Sample SizeStd Dev Sample Size mm Cob Diameter at mid-point 24.5 1.69 11 24.8 1.539 Cob Color 12 (Munsell code 10R 6/6) 12 (Munsell code 10R 5/6) DISEASERESISTANCE (Rate from 1 (most susceptible) to 9 (most resistant) LeafBlights, Wilts, and Local Infection Diseases Eyespot (Kabatiella zeae) 55 Northern Leaf Blight (Exserohilium turcicum) 3 Race 1 8 Race 1AGRONOMIC TRAITS Stay Green (at 65 days after anthesis) 6 2 (rate onscale from 1 = worst to 9 = excellent) % Dropped Ears (at 65 days afteranthesis) 0 .3 % Pre-anthesis Brittle snapping 0 .5 % Pre-anthesis RootLodging 0 0 % Post-anthesis Root Lodging 8 12 (at 65 days afteranthesis) In interpreting the foregoing color designations, referencemay be had to be made to the Munsell Glossy Book of Color, a standardcolor reference. Color codes: 1.light green, 2.medium green, 3.darkgreen, 4.very dark green, 5.green-yellow, 6.pale yellow, 7.yellow,8.yelow-orange, 9.salmon, 10.pink-orange, 11.pink, 12.light red,13.cherry red, 14.red, 15.red and white, 16.pale purple, 17.purple,18.colorless, # 19.white, 20.white capped, 21.buff, 22.tan, 23.brown,24.bronze, 25.variegated, 26.other. Std Dev = Standard Deviation

The invention also encompasses plants of inbred maize line NP2015 andparts thereof further comprising one or more specific, single genetraits which have been introgressed inbred maize line NP2015 fromanother maize line. Preferably, one or more new traits are transferredto inbred maize line NP2015, or, alternatively, one or more traits ofinbred maize line NP2015 are altered or substituted. The transfer (orintrogression) of the trait(s) into inbred maize line NP2015 is forexample achieved by recurrent selection breeding, for example bybackcrossing. In this case, inbred maize line NP2015 (the recurrentparent) is first crossed to a donor inbred (the non-recurrent parent)that carries the appropriate gene(s) for the trait(s) in question. Theprogeny of this cross is then mated back to the recurrent parentfollowed by selection in the resultant progeny for the desired trait(s)to be transferred from the non-recurrent parent. After three, preferablyfour, more preferably five or more generations of backcrosses with therecurrent parent with selection for the desired trait(s), the progenywill be heterozygous for loci controlling the trait(s) beingtransferred, but will be like the recurrent parent for most or almostall other genes (see, for example, Poehlman & Sleper (1995) BreedingField Crops, 4th Ed., 172-175; Fehr (1987) Principles of CultivarDevelopment, Vol. 1: Theory and Technique, 360-376, incorporated hereinby reference).

The laboratory-based techniques described above, in particular RFLP andSSR, are routinely used in such backcrosses to identify the progenieshaving the highest degree of genetic identity with the recurrent parent.This permits to accelerate the production of inbred maize lines havingat least 90%, preferably at least 95%, more preferably at least 99%genetic identity with the recurrent parent, yet more preferablygenetically identical to the recurrent parent, and further comprisingthe trait(s) introgressed from the donor patent. Such determination ofgenetic identity is based on molecular markers used in thelaboratory-based techniques described above. Such molecular markers arefor example those described in Boppenmaier, et al., “Comparisons amongstrains of inbreds for RFLPs”, Maize Genetics Cooperative Newsletter(1991) 65, pg. 90, incorporated herein by reference, or those availablefrom the University of Missouri database and the Brookhaven laboratorydatabase (see http://www.agron.missouri.edu, incorporated herein byreference). The last backcross generation is then selfed to give purebreeding progeny for the gene(s) being transferred The resulting plantshave essentially all of the morphological and physiologicalcharacteristics of inbred maize line NP2015, in addition to the singlegene trait(s) transferred to the inbred. The exact backcrossing protocolwill depend on the trait being altered to determine an appropriatetesting protocol. Although backcrossing methods are simplified when thetrait being transferred is a dominant allele, a recessive allele mayalso be transferred. In this instance it may be necessary to introduce atest of the progeny to determine if the desired trait has beensuccessfully transferred.

Many traits have been identified that are not regularly selected for inthe development of a new inbred but that can be improved by backcrossingtechniques. Examples of traits transferred to inbred maize line NP2015include, but are not limited to, waxy starch, herbicide tolerance,resistance for bacterial, fungal, or viral disease, insect resistance,enhanced nutritional quality, improved performance in an industrialprocess, altered reproductive capability, such as male sterility or malefertility, yield stability and yield enhancement. Other traitstransferred to inbred maize line NP2015 are for the production ofcommercially valuable enzymes or metabolites in plants of inbred maizeline NP2015. Traits transferred to maize inbred line NP2015 arenaturally occurring maize traits or are transgenic. Transgenes areoriginally introduced into a donor, non-recurrent parent using geneticengineering and transformation techniques well known in the art. Atransgene introgressed into maize inbred line NP2015 typically comprisesa nucleotide sequence whose expression is responsible or contributes tothe trait under the control of a promoter appropriate for the expressionof the nucleotide sequence at the desired time in the desired tissue orpart of the plant. Constitutive or inducible promoters are used. Thetransgene may also comprise other regulatory elements such as forexample translation enhancers or termination signals. In a preferredembodiment, the nucleotide sequence is the coding sequence of a gene andis transcribed and translated into a protein. In another preferredembodiment, the nucleotide sequence encodes an antisense RNA or a senseRNA that is not translated or only partially translated.

Where more than one trait are introgressed into inbred maize lineNP2015, it is preferred that the specific genes are all located at thesame genomic locus in the donor, non-recurrent parent, preferably, inthe case of transgenes, as part of a single DNA construct integratedinto the donor's genome. Alternatively, if the genes are located atdifferent genomic loci in the donor, non-recurrent parent, backcrossingallows to recover all of the morphological and physiologicalcharacteristics of inbred maize line NP2015 in addition to the multiplegenes in the resulting maize inbred line.

The genes responsible for a specific, single gene trait are generallyinherited through the nucleus. Known exceptions are, e.g. the genes formale sterility, some of which are inherited cytoplasmically, but stillact as single gene traits. In a preferred embodiment, a transgene to beintrogressed into maize inbred line NP2015 is integrated into thenuclear genome of the donor, non-recurrent parent. In another preferredembodiment, a transgene to be introgressed into maize inbred line NP2015is integrated into the plastid genome of the donor, non-recurrentparent.

In a preferred embodiment, a transgene whose expression results orcontributes to a desired trait to be transferred to maize inbred lineNP2015 comprises a virus resistance trait such as, for example, a MDMVstrain B coat protein gene whose expression confers resistance to mixedinfections of maize dwarf mosaic virus and maize chlorotic mottle virusin transgenic maize plants (Murry et al. Biotechnology (1993)11:1559-64, incorporated herein by reference). In another preferredembodiment, a transgene comprises a gene encoding an insecticidalprotein, such as, for example, a crystal protein of Bacillusthuringiensis or a vegetative insecticidal protein from Bacillus cereus,such as VIP3 (see for example Estruch et al. Nat Biotechnol (1997)15:137-41, incorporated herein by reference). In a preferred embodiment,an insecticidal gene introduced into maize inbred line NP2015 is aCry1Ab gene or a portion thereof, for example introgressed into maizeinbred line NP2015 from a maize line comprising a Bt-11 event asdescribed in PCT/US98/04984, incorporated herein by reference, or from amaize line comprising a 176 event as described in Koziel et al. (1993)Biotechnology 11: 194-200, incorporated herein by reference. In yetanother preferred embodiment, a transgene introgressed into maize inbredline NP2015 comprises a herbicide tolerance gene. For example,expression of an altered acetohydroxyacid synthase (AHAS) enzyme confersupon plants tolerance to various imidazolinone or sulfonamide herbicides(U.S. Pat. No. 4,761,373, incorporated herein by reference). In anotherpreferred embodiment, a non-transgenic trait conferring tolerance toimidazolinones is introgressed into maize inbred line NP2015 (e.g a “IT”or “IR” trait). U.S. Pat. No. 4,975,374, incorporated herein byreference, relates to plant cells and plants containing a gene encodinga mutant glutamine synthetase (GS) resistant to inhibition by herbicidesthat are known to inhibit GS, e.g. phosphinothricin and methioninesulfoximine. Also, expression of a Streptomyces bar gene encoding aphosphinothricin acetyl transferase in maize plants results in toleranceto the herbicide phosphinothricin or gluphosinate (U.S. Pat. No.5,489,520, incorporated herein by reference). U.S. Pat. No. 5,013,659,incorporated herein by reference, is directed to plants that express amutant acetolactate synthase (ALS) that renders the plants resistant toinhibition by sulfonylurea herbicides. U.S. Pat. No. 5,162,602,incorporated herein by reference, discloses plants tolerant toinhibition by cyclohexanedione and aryloxyphenoxypropanoic acidherbicides. The tolerance is conferred by an altered acetyl coenzyme Acarboxylase(ACCase). U.S. Pat. No. 5,554,798, incorporated herein byreference, discloses transgenic glyphosate tolerant maize plants, whichtolerance is conferred by an altered 5-enolpyruvyl-3-phosphoshikimate(EPSP) synthase gene. Also, tolerance to a protoporphyrinogen oxidaseinhibitor is achieved by expression of a tolerant protoporphyrinogenoxidase enzyme in plants (U.S. Pat. No. 5,767,373, incorporated hereinby reference).

In a preferred embodiment, a transgene introgressed into maize inbredline NP2015 comprises a gene conferring tolerance to a herbicide and atleast another nucleotide sequence encoding another trait, such as forexample, an insecticidal protein. Such combination of single gene traitsis for example a Cry1Ab gene and a bar gene. Specific transgenic eventsintrogressed into maize inbred line NP2015 are found athttp://www.aphis.usda.gov/bbep/bp/not_reg.html, incorporated herein byreference. These are for example introgressed from glyphosate tolerantevent GA21 (application number 9709901p), glyphosatetolerant/Lepidopteran insect resistant event MON 802 (application number9631701p), Lepidopteran insect resistant event DBT418 (applicationnumber 9629101p), male sterile event MS3 (application number 9522801p),Lepidopteran insect resistant event Bt11 (application number 9519501p),phosphinothricin tolerant event B16 (application number 9514501 p),Lepidopteran insect resistant event MON 80100 (application number9509301p), phosphinothricin tolerant events T14, T25 (application number9435701p), Lepidopteran insect resistant event 176 (application number9431901p).

The introgression of a Bt11 event into a maize line, such as maizeinbred line NP2015, by backcrossing is exemplified in PCT/US98/04984,incorporated herein by reference, and the present invention is directedto methods of introgressing a Bt11 event into maize inbred line NP2015using for example the markers described in PCT/US98/04984 and toresulting maize lines.

Direct selection may be applied where the trait acts as a dominanttrait. An example of a dominant trait is herbicide tolerance. For thisselection process, the progeny of the initial cross are sprayed with theherbicide prior to the backcrossing. The spraying eliminates any plantwhich do not have the desired herbicide tolerance characteristic, andonly those plants which have the herbicide tolerance gene are used inthe subsequent backcross. This process is then repeated for theadditional backcross generations.

INDUSTRIAL APPLICABILITY

This invention also is directed to methods for producing a maize plantby crossing a first parent maize plant with a second parent maize plantwherein either the first or second parent maize plant is a maize plantof inbred line NP2015 or a maize plant of inbred line NP2015 furthercomprising one or more single gene traits. Further, both first andsecond parent maize plants can come from the inbred maize line NP2015 oran inbred maize plant of NP2015 further comprising one or more singlegene traits. Thus, any such methods using the inbred maize line NP2015or an inbred maize plant of NP2015 further comprising one or more singlegene traits are part of this invention: selfing, backcrosses, hybridproduction, crosses to populations, and the like. All plants producedusing inbred maize line NP2015 or inbred maize plants of NP2015 furthercomprising one or more single gene traits as a parent are within thescope of this invention. Advantageously, inbred maize line NP2015 orinbred maize plants of NP2015 further comprising one or more single genetraits are used in crosses with other, different, maize inbreds toproduce first generation (F1) maize hybrid seeds and plants withsuperior characteristics.

In a preferred embodiment, seeds of inbred maize line NP2015 or seeds ofinbred maize plants of NP2015 further comprising one or more single genetraits are provided as an essentially homogeneous population of inbredcorn seeds. Essentially homogeneous populations of inbred seed are thosethat consist essentially of the particular inbred seed, and aregenerally purified free from substantial numbers of other seed, so thatthe inbred seed forms between about 90% and about 100% of the totalseed, and preferably, between about 95% and about 100% of the totalseed. Most preferably, an essentially homogeneous population of inbredcorn seed will contain between about 98.5%, 99%, 99.5% and about 100% ofinbred seed, as measured by seed grow outs. The population of inbredcorn seeds of the invention is further particularly defined as beingessentially free from hybrid seed. The inbred seed population may beseparately grown to provide an essentially homogeneous population ofplants of inbred maize line NP2015 or inbred maize plants of NP2015further comprising one or more single gene traits.

As used herein, the term “plant” includes plant cells, plantprotoplasts, plant cell tissue cultures from which maize plants can beregenerated, plant calli, plant clumps, and plant cells that are intactin plants or parts of plants, such as embryos, pollen, ovules, flowers,kernels, ears, cobs, leaves, husks, stalks, roots, root tips, anthers,silk, seeds and the like. Duncan, Williams, Zehr, and Widholm, Planta(1985) 165:322-332 reflects that 97% of the plants cultured thatproduced callus were capable of plant regeneration. Subsequentexperiments with both inbreds and hybrids produced 91% regenerablecallus that produced plants. In a further study in 1988, Songstad,Duncan & Widholm in Plant Cell Reports (1988), 7:262-265 reports severalmedia additions that enhance regenerability of callus of two inbredlines. Other published reports also indicated that “nontraditional”tissues are capable of producing somatic embryogenesis and plantregeneration. K. P. Rao, et al., Maize Genetics Cooperation Newsletter,60:64-65 (1986), refers to somatic embryogenesis from glume calluscultures and B. V. Conger, et al., Plant Cell Reports, 6:345-347 (1987)indicates somatic embryogenesis from the tissue cultures of maize leafsegments. Thus, it is clear from the literature that the state of theart is such that these methods of obtaining plants are, and were,“conventional” in the sense that they are routinely used and have a veryhigh rate of success.

Tissue culture of maize is described in European Patent Application,publication 160,390, incorporated herein by reference. Maize tissueculture procedures are also described in Green and Rhodes, “PlantRegeneration in Tissue Culture of Maize,” Maize for Biological Research(Plant Molecular Biology Association, Charlottesville, Va. 1982, at367-372) and in Duncan, et al., “The Production of Callus Capable ofPlant Regeneration from Immature Embryos of Numerous Zea maysGenotypes,” 165 Planta 322-332 (1985). Thus, another aspect of thisinvention is to provide cells which upon growth and differentiationproduce maize plants having the physiological and morphologicalcharacteristics of inbred maize line NP2015. In a preferred embodiment,cells of inbred maize line NP2015 are transformed genetically, forexample with one or more genes described above, for example by using atransformation method described in PCT/US98/04984, incorporated hereinby reference, and transgenic plants of inbred maize line NP2015 areobtained and used for the production of hybrid maize plants.

Maize is used as human food, livestock feed, and as raw material inindustry. The food uses of maize, in addition to human consumption ofmaize kernels, include both products of dry- and wet-milling industries.The principal products of maize dry milling are grits, meal and flour.The maize wet-milling industry can provide maize starch, maize syrups,and dextrose for food use. Maize oil is recovered from maize germ, whichis a by-product of both dry- and wet-milling industries.

Maize, including both grain and non-grain portions of the plant, is alsoused extensively as livestock feed, primarily for beef cattle, dairycattle, hogs, and poultry. Industrial uses of maize include productionof ethanol, maize starch in the wet-milling industry and maize flour inthe dry-milling industry. The industrial applications of maize starchand flour are based on functional properties, such as viscosity, filmformation, adhesive properties, and ability to suspend particles. Themaize starch and flour have application in the paper and textileindustries. Other industrial uses include applications in adhesives,building materials, foundry binders, laundry starches, explosives,oil-well muds, and other mining applications. Plant parts other than thegrain of maize are also used in industry: for example, stalks and husksare made into paper and wallboard and cobs are used for fuel and to makecharcoal.

The seed of inbred maize line NP2015 or of inbred maize line NP2015further comprising one or more single gene traits, the plant producedfrom the inbred seed, the hybrid maize plant produced from the crossingof the inbred, hybrid seed, and various parts of the hybrid maize plantcan be utilized for human food, livestock feed, and as a raw material inindustry.

PERFORMANCE EXAMPLES OF MAIZE INBRED LINE NP2015

In the examples that follow, the traits and characteristics of inbredmaize line NP2015 are presented as an inbred comparisons per se and asinbred by tester comparisons. The data presented is for keycharacteristics and traits and is reported from experiments where thecompared lines where grown side-by-side.

Inbred Comparisons

The data in table 2A show for example that inbred NP2015 issignificantly higher to the top ear node than inbred A619, that inbredNP2015 has significantly shorter tassel from top leaf collar to tasseltip than inbred A619, that inbred NP2015 has significantly thinnerkernels than inbred A619, that inbred NP2015 has significantly lessround kernels on 13/64 slotted screen than inbred A619 and that inbredNP2015 has significantly less leaf longitudinal creases than inbredA619.

TABLE 2A Comparison of inbreds NP2015 and A619 PLHCN ERHCN HU1SN HU5SNHU9SN HUPSN HUPLN PLQUR EARPN SHLNN LTEIN ERLWN NP2015 168 66 1181 12121239 1202 46 6 1 10 10 9 A619 168 41 1227 1308 1296 1257 55 7 1 8 12 10Grand Mean 168 54 1204 1260 1268 1230 50 6 1 9 11 9 Trials w/data 3 3 33 3 3 3 3 3 3 3 3 LSD 56 15 80 135 83 68 19 1 0 3 9 2 CV % 6 24 1 1 1 139 13 20 33 11 20 Probability % 98 0 13 9 10 8 34 8 0 25 52 60 ERLLNLAERN ANGBN LTBRN TBANN LTASN ERLNN ERDIN EWGTN KRRWN KRLNN KRWDN NP201567 5 38 8 45 28 15 39 118 12 11 9 A619 69 5 38 8 41 39 13 39 89 13 11 9Grand Mean 68 5 38 8 43 33 14 39 103 13 11 9 Trials w/data 3 3 3 3 3 3 33 3 3 3 3 LSD 15 4 8 7 13 2 12 25 106 7 1 1 CV % 3 13 19 18 27 6 7 9 1311 6 8 Probability % 64 86 98 81 59 0 52 91 37 49 72 92 KRDPN KRPRNK100N COBDN APBRR LSPUR MLWVR LFLCR HEPSR KRNAR ETAPR NP2015 4 19 33 243 3 6 3 1 2 2 A619 5 61 32 27 2 2 6 5 1 2 2 Grand Mean 4 40 33 25 3 2 64 1 2 2 Trials w/data 3 3 3 3 3 3 3 3 3 3 3 LSD 1 15 4 16 1 4 1 1 1 0 0CV % 18 33 10 8 12 33 16 26 27 4 19 Probability % 0 0 42 55 18 23 38 042 0 11

The data in table 2B show for example that inbred NP2015 issignificantly shorter to the top ear node than inbred B64, that inbredNP2015 is shedding pollen and extruding silk significantly earlier thaninbred B64 and that inbred NP2015 has a significantly shorter tasselfrom top leaf collar to tassel tip than inbred B64.

TABLE 2B Comparison of inbreds NP2015 and B64 LRTLP PLHCN ERHCN HU1SNHU5SN HU9SN HUPSN STGRP HUPLN PLQUR EARPN LTEIN ERLWN NP2015 11 168 661181 1212 1239 1202 6 46 6 1 10 9 B64 50 212 95 1510 1552 1590 1549 8 605 1 13 8 Grand Mean 27 190 80 1312 1348 1380 1341 7 52 6 1 12 9 Trialsw/data 3 3 3 3 3 3 3 2 3 3 3 3 3 LSD 29 47 15 32 19 19 2 8 2 CV % 81 516 0 39 14 18 11 21 Probability % 2 6 0 0 0 0 0 50 17 65 82 29 57 ERLLNLAERN ANGBN LTBRN TBANN LTASN APBRR LSPUR MLWVR LFLCR HSKTR HEPSR NP201567 5 38 8 45 28 3 3 6 3 5 1 B64 95 5 45 7 46 44 3 7 6 2 9 1 Grand Mean81 5 41 7 46 36 3 5 6 3 7 1 Trials w/data 3 3 3 3 3 3 3 3 3 3 2 3 LSD 161 8 2 13 2 3 15 1 1 13 1 CV % 3 12 18 19 26 5 11 17 17 39 0 27Probability % 2 17 16 34 87 0 84 21 25 56 16 42

The data in table 2C show for example that inbred NP2015 is sheddingpollen significantly later than inbred CM105, that inbred NP2015 hassignificantly shorter tassel from top leaf collar to tassel tip thaninbred CM105, that inbred NP2015 has significantly longer kernels thaninbred CM105, that inbred NP2015 has significantly wider kernels thaninbred CM105, that inbred NP2015 has significantly heavier kernels thaninbred CM105 and that inbred NP2015 has a significantly less leaf sheathpubescence of second leaf above the ear (at anthesis) than inbred CM105.

TABLE 2C Comparison of inbreds NP2015 and CM105 PLHCN ERHCN HU1SN HU5SNHU9SN HUPSN HUPLN PLQUR EARPN SHLNN HSKCR LTEIN NP2015 168 66 1181 12121239 1202 46 6 1 10 2 10 CM105 174 62 1116 1183 1186 1152 57 6 1 8 3 12Grand Mean 171 64 1149 1197 1213 1177 52 6 1 9 3 11 Trials w/data 3 3 33 3 3 3 3 3 3 2 3 LSD 12 15 16 212 19 16 19 1 0 3 13 9 CV % 6 20 1 1 1 138 14 19 32 0 12 Probability % 35 55 0 62 0 0 22 49 2 30 50 53 ERLWNERLLN LAERN ANGBN LTBRN TBANN LTASN ERLNN ERDIN EWGTN KRRWN KRLNN NP20159 67 5 38 8 45 28 15 39 118 12 11 CM105 8 80 5 51 7 47 34 13 34 77 13 10Grand Mean 8 73 5 45 7 46 31 14 37 97 13 10 Trials w/data 3 3 3 3 3 3 33 3 3 3 3 LSD 2 11 1 38 2 13 2 10 4 73 2 1 CV % 22 3 13 17 20 25 6 7 1014 11 6 Probability % 18 4 70 29 19 77 0 46 5 14 28 0 KRWDN KRDPN KRPRNK100N COBDN APBRR LSPUR MLWVR LFLCR HSKTR HEPSR NP2015 9 4 19 33 24 3 36 3 5 1 CM105 8 4 31 25 24 3 6 5 4 4 2 Grand Mean 8 4 25 29 24 3 5 6 3 42 Trials w/data 3 3 3 3 3 3 3 3 3 2 3 LSD 1 1 15 4 2 2 1 1 1 44 4 CV % 919 51 12 9 10 17 17 30 0 17 Probability % 0 19 9 0 79 74 0 3 8 74 42

Inbred By Tester Comparison

The results in Table 3A compare inbred NP2015 and inbreda when eachinbred is crossed to the same tester line. For example, the NP2015hybrid has significantly higher grain yield expressed as bushels peracre adjusted to 15.5% grain moisture than the inbredA hybrid, theNP2015 hybrid has significantly higher grain moisture at harvest thanthe inbredA hybrid, the NP2015 hybrid has significantly more emergedplants prior to thinning than the inbredA hybrid.

TABLE 3A Comparison of inbred NP2015 crossed to tester inbredX andinbredA crossed to tester inbredX YBUAN MST_P STD_P EMRGP STKLP LRTLPERTLP PLHCN ERHCN HU5SN INBRED X/NP2015 155.6 22.2 97 93.4 1 0 3 227 941203 INBRED X/INBRED A 140.9 19.4 95 90.2 1 7 10 213 90 1190 Grand Mean148.3 20.8 96 91.8 1 4 7 220 92 1196 Trials w/data 47 48 51 48 35 13 125 5 5 LSD 5 0.5 1 1.3 1 10 6 46 9 18 CV % 11.6 5.6 4 4.8 350 112 156 911 2 Probability % 0 0 1 0 64 16 3 44 32 15 HUPSN INTLR TSTWN SVGRRPLTAR GRQUR EMRGR ERGRR INBRED X/NP2015 1202 2.9 58.8 2.9 4 2.9 3.2 2.5INBRED X/INBRED A 1181 3.4 59 4 2.5 2 4.1 3 Grand Mean 1191 3.2 58.9 3.53.3 2.5 3.7 2.8 Trials w/data 5 11 39 8 4 5 5 11 LSD 17 0.5 0.7 0.8 2.10.7 1 0.4 CV % 2 24.6 3.8 18.9 28.2 15.8 29.4 23.8 Probability % 1 4.464.8 1.6 10.2 2.1 5.9 0.6 STD_P: % Stand, EMRGP: % emerged plants priorto thinning, TSTWN: test weight in LBS/BU, SVGRR: seedling vigor (3-5leaf stage), PLTAR: plant Appearance, GRQUR grain quality, EMRGR: earlyemergence vigor (prior to 3-leaf stage), ERGRR: early growth (6+ leafstage).

The results in Table 3B compare inbred NP2015 and inbredB when eachinbred is crossed to the same tester line. For example, the NP2015hybrid has significantly higher grain yield expressed as bushels peracre adjusted to 15.5% grain moisture than the inbredB hybrid, theNP2015 hybrid has significantly higher grain moisture at harvest thanthe inbredB hybrid, the NP2015 hybrid has a significantly higher % standthan the inbredB hybrid, the NP2015 hybrid has significantly moreemerged plants prior to thinning than the inbredB hybrid, the NP2015hybrid is significantly later to shed pollen and extrude silk than theinbredA hybrid.

TABLE 3B Comparison of inbred NP2015 crossed to tester inbredX andinbredB crossed to tester inbredX YBUAN MST_P STD_P EMRGP PLHCN ERHCNHU5SN HUBLN HUPSN INTLR INBRED X/NP2015 153.7 24.2 97 93.8 239 101 11851900 1187 3.2 INBRED X/INBRED B 144.9 23.1 95 89.8 246 93 1148 1926 11433.5 Grand Mean 149.4 23.7 96 91.8 242 97 1167 1913 1165 3.4 Trialsw/data 75 76 79 76 9 9 7 1 7 12 LSD 3.7 0.4 1 1 11 7 14 61 13 0.5 CV %10.8 4.9 4 4.8 7 11 2 2 1 23.2 Probability % 0 0 0 0 19 3 0 1 0 18.4TSTWN STGRP SVGRR PLTAR GRQUR PSTSN PSTSP EMRGR ERGRR TWFKN INBREDX/NP2015 59.4 34 3.2 3.9 2.9 0.6 15 9.5 2.8 62 INBRED X/INBRED B 60.3 423.1 2.6 2.1 9.7 27 9.9 3.3 65 Grand Mean 59.8 38 3.1 3.3 2.5 5.2 21 9.73 63 Trials w/data 60 3 14 7 8 2 36 9 16 3 LSD 0.6 11 0.3 2.1 0.3 6.4 101.5 0.5 1 CV % 3.7 25 20.7 45.5 11.7 88 101 12.3 21.2 2 Probability %0.2 13 75 17.8 0 0.6 3 58 5 0 HUBLN: heat units to physiologicalmaturity, PSTSN: push test for stalk/root quality on erect plants perrow, PSTSP: push test for stalk/root quality on erect plants, TWFKN:test weight in Kg/Fix volume in cubic centimeter.

DEPOSIT

Applicants have made a deposit of at least 2500 seeds of Inbred CornLine NP2015 with the American Type Culture Collection (ATCC), Manassas,Va., 20110-2209 U.S.A., ATCC Deposit No:203773. The seeds deposited withthe ATCC on Feb. 12, 1999 were taken from the deposit maintained byNovartis Corporation, 3054 Cornwallis Road, Research Triangle Park, N.C.27709, since prior to the filing date of this application. This depositof the Inbred Maize Line NP2015 will be maintained in the ATCCdepository, which is a public depository, for a period of 30 years, or 5years after the most recent request, or for the effective life of thepatent, whichever is longer, and will be replaced if it becomesnonviable during that period. Additionally, Applicants have satisfiedall the requirements of 37 C.F.R. §§1.801-1.809, including providing anindication of the viability of the sample. Applicants impose norestrictions on the availability of the deposited material from theATCC; however, Applicants have no authority to waive any restrictionsimposed by law on the transfer of biological material or itstransportation in commerce. Applicants do not waive any infringement ofits rights granted under this patent or under the Plant VarietyProtection Act (7 USC 2321 et seq.). U.S. Plant Variety Protection ofInbred Maize Line NP2015 has been applied for under application Ser. No.9800391.

The foregoing invention has been described in detail by way ofillustration and example for purposes of clarity and understanding.However, it will be obvious that certain changes and modifications suchas single gene modifications and mutations, somaclonal variants, variantindividuals selected from large populations of the plants of the instantinbred and the like may be practiced within the scope of the invention,as limited only by the scope of the appended claims.

What is claimed is:
 1. Seed of maize inbred line NP2015 having beendeposited under ATCC Accession No:
 203773. 2. A maize plant, or partsthereof, of inbred line NP2015, seed of said line having been depositedunder ATCC Accession No:
 203773. 3. Pollen of the plant of claim
 2. 4.An ovule of the plant of claim
 2. 5. A maize plant, or parts thereof,having all the physiological and morphological characteristics of aplant of inbred line NP2015, seed of said line having been depositedunder ATCC Accession No:
 203773. 6. A male sterile maize plant, or partsthereof, otherwise having all the physiological and morphologicalcharacteristics of a plant of inbred line NP2015, seed of said linehaving been deposited under ATCC Accession No:
 203773. 7. A maize plant,or parts thereof, of inbred line NP2015, seed of said line having beendeposited under ATCC Accession No: 203773, further comprising one ormore single gene transferred traits.
 8. A maize plant according to claim7, wherein said single gene transferred trait comprises a gene which isintroduced by transgenic methods.
 9. A maize plant according to claim 7,wherein said single gene transferred trait comprises a gene conferringupon said maize plant tolerance to a herbicide.
 10. A maize plantaccording to claim 9, wherein said herbicide is glyphosate, gluphosinateor a protoporphyrinogen oxidase inhibitor.
 11. A maize plant accordingto claim 7, wherein said single gene transferred trait comprises a geneconferring upon said maize plant insect resistance, disease resistanceor virus resistance.
 12. A maize plant according to claim 11, whereinsaid gene conferring upon said maize plant insect resistance is aBacillus thuringiensis Cry1Ab gene.
 13. A maize plant according to claim12, further comprising a bar gene.
 14. A maize plant according to claim12, wherein said Cry1Ab gene is introgressed into said maize plant froma maize line comprising a Bt-11 event or a 176 event.
 15. A tissueculture of regenerable cells of a maize plant of inbred line NP2015,seed of said inbred line having been deposited under ATCC Accession No:203773.
 16. A tissue culture according to claim 15, the regenerablecells being selected from the group consisting of embryos, meristems,pollen, leaves, anthers, roots, root tips, silk, flowers, kernels, ears,cobs, husks and stalks, or being protoplasts or callus derivedtherefrom.
 17. A maize plant regenerated from the tissue culture ofclaim 15, capable of expressing all the morphological and physiologicalcharacteristics of inbred line NP2015, seed of said inbred line havingbeen deposited under ATCC Accession No:
 203773. 18. A method forproducing maize seed comprising crossing a first parent maize plant witha second parent maize plant and harvesting the resultant firstgeneration maize seed, wherein said first or second parent maize plantis the inbred maize plant of claim
 2. 19. A method according to claim18, wherein said first parent maize plant is different from said secondparent maize plant, wherein said resultant seed is a first generation(F1) hybrid maize seed.
 20. A method according to claim 18, whereininbred maize plant of claim 2 is the female parent.
 21. A methodaccording to claim 18, wherein inbred maize plant of claim 2 is the maleparent.
 22. An F1 hybrid seed produced by the method of claim
 19. 23. AnF1 hybrid plant, or parts thereof, grown from the seed of claim
 22. 24.A method for producing maize seed comprising crossing a first parentmaize plant with a second parent maize plant and harvesting theresultant first generation maize seed, wherein said first or secondparent maize plant is the inbred maize plant of claim
 5. 25. A methodaccording to claim 24, wherein said first parent maize plant isdifferent from said second parent maize plant, wherein said resultantseed is a first generation (F1) hybrid maize seed.
 26. A methodaccording to claim 24, wherein inbred maize plant of claim 5 is thefemale parent.
 27. A method according to claim 26, wherein inbred maizeplant of claim 5 is the male parent.
 28. An F1 hybrid seed produced bythe method of claim
 25. 29. An F1 hybrid plant, or parts thereof, grownfrom the seed of claim
 28. 30. A method for producing maize seedcomprising crossing a first parent maize plant with a second parentmaize plant and harvesting the resultant first generation maize seed,wherein said first or second parent maize plant is the inbred maizeplant of claim
 7. 31. A method according to claim 30, wherein said firstparent maize plant is different from said second parent maize plant,wherein said resultant seed is a first generation (F1) hybrid maizeseed.
 32. A method according to claim 30, wherein inbred maize plant ofclaim 7 is the female parent.
 33. A method according to claim 30,wherein inbred maize plant of claim 7 is the male parent.
 34. An F1hybrid seed produced by the method of claim
 31. 35. An F1 hybrid plant,or parts thereof, grown from the seed of claim
 34. 36. A methodcomprising: (a) planting a collection of seed comprising seed of ahybrid, one of whose parents is inbred line NP2015, seed of said linehaving been deposited under ATCC Accession No: 203773, or a maize planthaving all the physiological and morphological characteristics of inbredline NP2015, said collection also comprising seed of said inbred; (b)growing plants from said collection of seed; (c) identifying said inbredplants; (d) selecting said inbred plant; and (e) controlling pollinationin a manner which preserves the homozygosity of said inbred plant.
 37. Amethod according to claim 36, wherein said one parent is inbred maizeline NP2015, seed of said line having been deposited under ATCCAccession No: 203773, further comprising one or more single genetransferred traits.
 38. The process of claim 36 wherein said step ofidentifying said inbred plant comprises: identifying plants withdecreased vigor.
 39. A method comprising introgressing one or moresingle gene traits into inbred maize line NP2015, seed of said linehaving been deposited under ATCC Accession No: 203773, using one or moremarkers for marker assisted selection among maize lines to be used in amaize breeding program, the markers being associated with said one ormore single gene traits, wherein the resulting maize line is inbred lineNP2015 further comprising said one or more single gene transferredtraits.
 40. A method according to claim 39, wherein said one or moresingle gene traits comprises a Cry1Ab gene and said markers compriseZ1B3 and UMC150a.
 41. A maize plant according to claim 7, wherein saidsingle gene transferred trait comprises a gene which is first introducedby transgenic methods into a maize line different from said inbred maizeline NP2015 and then introgressed into said inbred maize line NP2015.42. Seeds of a plant according to claim 7.